关于 netbeans:Apache Derby – java.sql.SQLException: 无法启动数据库

codeneng 2023-03-28 原文

Apache Derby - java.sql.SQLException: Failed to start database

首先，这是我第一次使用 Apache Derby。我正在使用 netbeans，愿意使用嵌入式 apache derby，并按照以下教程配置和安装数据库。然后，我使用项目属性将 derby.jar 文件附加到我的项目中。

http://netbeans.org/kb/docs/ide/java-db.html#starting

所附图片将在 netbeans 中显示我的数据库状态

我的数据库名称是"联系人"。表名是"FRIENDS"。

以下是我的测试代码

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**DatabaseConnector.java**

import java.sql.*;

public class DataBaseConnector
{
private Connection con;

public DataBaseConnector()
{

}

private void createConnection()
{
try
{
Class.forName("org.apache.derby.jdbc.EmbeddedDriver");
con = DriverManager.getConnection("jdbc:derby:C:/Users/yohan/.netbeans-derby/contact","yohan","xyz");
}
catch(Exception e)
{
e.printStackTrace();
}
}

private void closeConnection()
{
try
{
con.close();
}
catch(Exception e)
{
e.printStackTrace();
}
}

public void insertData(int id, String firstName, String lastName)
{
createConnection();
try
{
PreparedStatement ps = con.prepareStatement("insert into FRIENDS values(?,?,?)");
ps.setInt(1, id);
ps.setString(1, firstName);
ps.setString(2, lastName);

int result = ps.executeUpdate();

if(result>0)
{
System.out.println("Data Inserted");
}
else
{
System.out.println("Something happened");
}
}
catch(Exception e)
{
e.printStackTrace();
}
finally
{
closeConnection();
}
}

}

DatabaseUI.java

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import java.awt.event.*;
import javax.swing.*;
import java.awt.*;

public class DatabaseUI extends JFrame
{
private JLabel firstName, id, lastName;
private JTextField idTxt, firstNameTxt, lastNameTxt;
private JButton ok;

public DatabaseUI()
{
firstName = new JLabel("First Name:");
lastName = new JLabel("Last Name:");
id = new JLabel("ID:");

firstNameTxt = new JTextField(10);
lastNameTxt = new JTextField(10);
idTxt = new JTextField(10);

ok = new JButton("OK");
ok.addActionListener(new OKAction());

JPanel centerPanel = new JPanel();
centerPanel.setLayout(new GridLayout(4,2));
centerPanel.add(id);
centerPanel.add(idTxt);
centerPanel.add(firstName);
centerPanel.add(firstNameTxt);
centerPanel.add(lastName);
centerPanel.add(lastNameTxt);
centerPanel.add(new JPanel());
centerPanel.add(ok);

getContentPane().add(centerPanel,"Center");

this.pack();
this.setVisible(true);

}

private class OKAction implements ActionListener
{
public void actionPerformed(ActionEvent ae)
{
DataBaseConnector db = new DataBaseConnector();

int id = Integer.parseInt(idTxt.getText());

db.insertData(id, firstNameTxt.getText().trim(), lastNameTxt.getText().trim());
}
}

public static void main(String[]args)
{
new DatabaseUI();
}
}

但是，当我尝试将数据插入数据库时??，它给了我以下错误

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run:
java.sql.SQLException: Failed to start database 'C:/Users/yohan/.netbeans-derby/contact' with class loader sun.misc.Launcher$AppClassLoader@1050169, see the next exception for details.
at org.apache.derby.impl.jdbc.SQLExceptionFactory40.getSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.Util.newEmbedSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.Util.seeNextException(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedConnection.bootDatabase(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedConnection.<init>(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedConnection30.<init>(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedConnection40.<init>(Unknown Source)
at org.apache.derby.jdbc.Driver40.getNewEmbedConnection(Unknown Source)
at org.apache.derby.jdbc.InternalDriver.connect(Unknown Source)
at org.apache.derby.jdbc.AutoloadedDriver.connect(Unknown Source)
at java.sql.DriverManager.getConnection(DriverManager.java:579)
at java.sql.DriverManager.getConnection(DriverManager.java:221)
at DataBaseConnector.createConnection(DataBaseConnector.java:17)
at DataBaseConnector.insertData(DataBaseConnector.java:40)
at DatabaseUI$OKAction.actionPerformed(DatabaseUI.java:53)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
at java.awt.Component.processMouseEvent(Component.java:6504)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3321)
at java.awt.Component.processEvent(Component.java:6269)
at java.awt.Container.processEvent(Container.java:2229)
at java.awt.Component.dispatchEventImpl(Component.java:4860)
at java.awt.Container.dispatchEventImpl(Container.java:2287)
at java.awt.Component.dispatchEvent(Component.java:4686)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4832)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4492)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4422)
at java.awt.Container.dispatchEventImpl(Container.java:2273)
at java.awt.Window.dispatchEventImpl(Window.java:2713)
at java.awt.Component.dispatchEvent(Component.java:4686)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:707)
at java.awt.EventQueue.access$000(EventQueue.java:101)
at java.awt.EventQueue$3.run(EventQueue.java:666)
at java.awt.EventQueue$3.run(EventQueue.java:664)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
at java.awt.EventQueue$4.run(EventQueue.java:680)
at java.awt.EventQueue$4.run(EventQueue.java:678)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:677)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:211)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:90)
Caused by: java.sql.SQLException: Failed to start database 'C:/Users/yohan/.netbeans-derby/contact' with class loader sun.misc.Launcher$AppClassLoader@1050169, see the next exception for details.
at org.apache.derby.impl.jdbc.SQLExceptionFactory.getSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.SQLExceptionFactory40.wrapArgsForTransportAcrossDRDA(Unknown Source)
... 51 more
Caused by: java.sql.SQLException: Another instance of Derby may have already booted the database C:\\Users\\yohan\\.netbeans-derby\\contact.
at org.apache.derby.impl.jdbc.SQLExceptionFactory.getSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.SQLExceptionFactory40.wrapArgsForTransportAcrossDRDA(Unknown Source)
at org.apache.derby.impl.jdbc.SQLExceptionFactory40.getSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.Util.generateCsSQLException(Unknown Source)
... 48 more
Caused by: ERROR XSDB6: Another instance of Derby may have already booted the database C:\\Users\\yohan\\.netbeans-derby\\contact.
at org.apache.derby.iapi.error.StandardException.newException(Unknown Source)
at org.apache.derby.impl.store.raw.data.BaseDataFileFactory.privGetJBMSLockOnDB(Unknown Source)
at org.apache.derby.impl.store.raw.data.BaseDataFileFactory.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at org.apache.derby.impl.store.raw.data.BaseDataFileFactory.getJBMSLockOnDB(Unknown Source)
at org.apache.derby.impl.store.raw.data.BaseDataFileFactory.boot(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.startModule(Unknown Source)
at org.apache.derby.iapi.services.monitor.Monitor.bootServiceModule(Unknown Source)
at org.apache.derby.impl.store.raw.RawStore.boot(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.startModule(Unknown Source)
at org.apache.derby.iapi.services.monitor.Monitor.bootServiceModule(Unknown Source)
at org.apache.derby.impl.store.access.RAMAccessManager.boot(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.startModule(Unknown Source)
at org.apache.derby.iapi.services.monitor.Monitor.bootServiceModule(Unknown Source)
at org.apache.derby.impl.db.BasicDatabase.bootStore(Unknown Source)
at org.apache.derby.impl.db.BasicDatabase.boot(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.bootService(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.startProviderService(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.findProviderAndStartService(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.startPersistentService(Unknown Source)
at org.apache.derby.iapi.services.monitor.Monitor.startPersistentService(Unknown Source)
... 48 more
java.lang.NullPointerException
at DataBaseConnector.insertData(DataBaseConnector.java:43)
at DatabaseUI$OKAction.actionPerformed(DatabaseUI.java:53)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
at java.awt.Component.processMouseEvent(Component.java:6504)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3321)
at java.awt.Component.processEvent(Component.java:6269)
at java.awt.Container.processEvent(Container.java:2229)
at java.awt.Component.dispatchEventImpl(Component.java:4860)
at java.awt.Container.dispatchEventImpl(Container.java:2287)
at java.awt.Component.dispatchEvent(Component.java:4686)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4832)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4492)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4422)
at java.awt.Container.dispatchEventImpl(Container.java:2273)
at java.awt.Window.dispatchEventImpl(Window.java:2713)
at java.awt.Component.dispatchEvent(Component.java:4686)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:707)
at java.awt.EventQueue.access$000(EventQueue.java:101)
at java.awt.EventQueue$3.run(EventQueue.java:666)
at java.awt.EventQueue$3.run(EventQueue.java:664)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
at java.awt.EventQueue$4.run(EventQueue.java:680)
at java.awt.EventQueue$4.run(EventQueue.java:678)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:677)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:211)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:90)
java.lang.NullPointerException
at DataBaseConnector.closeConnection(DataBaseConnector.java:29)
at DataBaseConnector.insertData(DataBaseConnector.java:65)
at DatabaseUI$OKAction.actionPerformed(DatabaseUI.java:53)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
at java.awt.Component.processMouseEvent(Component.java:6504)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3321)
at java.awt.Component.processEvent(Component.java:6269)
at java.awt.Container.processEvent(Container.java:2229)
at java.awt.Component.dispatchEventImpl(Component.java:4860)
at java.awt.Container.dispatchEventImpl(Container.java:2287)
at java.awt.Component.dispatchEvent(Component.java:4686)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4832)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4492)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4422)
at java.awt.Container.dispatchEventImpl(Container.java:2273)
at java.awt.Window.dispatchEventImpl(Window.java:2713)
at java.awt.Component.dispatchEvent(Component.java:4686)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:707)
at java.awt.EventQueue.access$000(EventQueue.java:101)
at java.awt.EventQueue$3.run(EventQueue.java:666)
at java.awt.EventQueue$3.run(EventQueue.java:664)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
at java.awt.EventQueue$4.run(EventQueue.java:680)
at java.awt.EventQueue$4.run(EventQueue.java:678)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:677)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:211)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:90)
BUILD SUCCESSFUL (total time: 12 seconds)

这是为什么？请帮忙！

除了第一个主要问题，我想再问两个问题。

我必须在这里给出数据库的显式位置作为连接。但是，当我把它交给客户时，我该怎么做呢？

我必须使用 netbeans 手动启动数据库连接。反正有没有自动启动数据库连接？使用代码？

请帮帮我。谢谢

这似乎相关："另一个 Derby 实例可能已经启动了数据库 C:\\\\\\\\Users\\\\\\\\yohan\\\\\\\\.netbeans-derby\\\\\\\\contact."
是的..但是没有！或者，至少，我不是自己做的！代码中是否有任何错误？

您的数据已连接断开右键单击 -> 断开连接现在尝试它，

它肯定会起作用的。

这对我有用。我正在运行连接到数据库的 Web 应用程序，但我也无法通过 IDE 连接。但是一旦我停止了应用程序，我就可以从 IDE 连接。
如何断开数据库？我已重命名数据库以解决问题，因为我不知道如何停止连接(即使在系统重启后我也遇到了错误，所以我不得不重命名数据库)

您的程序包含一些误解和错误分配！

从您的图像中您可以看到您的 DATABASE = contactDB 不是联系人。
"jdbc:derby:C:/Users/yohan/.netbeans-derby/contact" 是错误的
"jdbc:derby:C:/Users/yohan/.netbeans-derby/contactDB" 现在只有数据库是正确的。
错误：另一个 Derby 实例可能已经启动了数据库 C:\\\\\\\\Users\\\\\\\\yohan.netbeans-derby\\\\\\\\contact.
对于 Con.String 最好不要使用 PATH
将工作 "jdbc:derby://localhost:1527/C:/Users/yohan/.netbeans-derby/contactDB","yohan","xyz"
更好的是 "jdbc:derby://localhost:1527/contactDB","yohan","xyz"

最好指定表的完整路径。否则它只能在 Netbeans 中工作，具有已打开的表和默认模式。

准备声明
仅在 Netbeans con.prepareStatement("insert into FRIENDS values(?,?,?)");
更好的是 con.prepareStatement("insert into APP.FRIENDS values(?,?,?)");

现在看看这个！

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ps.setInt(1, id);
ps.setString(1, firstName);
ps.setString(2, lastName);

首先，您使用 setInt() 设置 id。
第二现在您使用字符串 setString() 设置 id ( firstName !!!!!)
最后，您在 ps 中使用 lastName 和 lastName 覆盖 firstName。是空的。

这会给你下一个错误

发生错误时最好不要继续运行程序。错误列表会变长。很难读。在您的情况下，第一个错误在 createConnection 中并在 !!

错误创建连接
错误 con.prepareStatement("...
错误 ps.executeUpdate()
错误关闭连接()

用 boolean 和 if 测试它！

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private boolean createConnection()
{
try
{
Class.forName("org.apache.derby.jdbc.EmbeddedDriver");
con = DriverManager.getConnection("jdbc:derby://localhost:1527/contactDB","yohan","xyz");
}
catch(Exception e)
{
System.out.println("Error getConnection");
return false;
}
return true;
}

如果连接失败，无需继续运行。

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public void insertData(int id, String firstName, String lastName)
{
if (createConnection()) {
try
{
PreparedStatement ps = con.prepareStatement("INSERT INTO APP.FRIENDS values(?,?,?)");
ps.setInt(1, id);
ps.setString(2, firstName);
ps.setString(3, lastName);
[...]

希望对你有所帮助。

非常感谢您的回复。对此，我真的非常感激。我编辑了它，连接失败！但是，contactDB 是 URL 的名称，而不是数据库的名称。数据库名称是"联系人"。我按照教程做到了
看看你的图片 --contactDB--APP--FRIENDS
连接失败并出现"java.sql.SQLException：找不到适合 jdbc:derby://localhost:1527/C:/Users/yohan/.netbeans-derby/c??ontactDB 的驱动程序"
将库 java DB Driver 添加到您的项目(属性 -- 库 -- 添加库...)
如果您的 Netbeans 中没有库 java DB Driver 则手动将 derbyclient.jar 和 derbynet.jar 添加到您的项目中
谢谢！有效！我必须遵循您提到的所有建议和编辑。但是，数据库名称是联系方式，我必须将联系数据库替换为联系方式才能完成这项工作。非常感谢您的帮助！！无论如何，对于嵌入式数据库来说，本地主机连接 URL 是否可以？

您的数据库已经连接，您必须断开连接。右键单击->断开连接。
现在再试一次，它肯定会起作用。

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